1 files changed, 37 insertions, 0 deletions
diff --git a/testing/mozbase/mozlog/tests/test_capture.py b/testing/mozbase/mozlog/tests/test_capture.py
new file mode 100644
index 0000000000..4adbda4180
--- /dev/null
+++ b/testing/mozbase/mozlog/tests/test_capture.py
@@ -0,0 +1,37 @@
+import sys
+import unittest
+
+import mozunit
+from mozlog import capture, structuredlog
+from test_structured import TestHandler
+
+
+class TestCaptureIO(unittest.TestCase):
+    """Tests expected logging output of CaptureIO"""
+
+    def setUp(self):
+        self.logger = structuredlog.StructuredLogger("test")
+        self.handler = TestHandler()
+        self.logger.add_handler(self.handler)
+
+    def test_captureio_log(self):
+        """
+        CaptureIO takes in two arguments. The second argument must
+        be truthy in order for the code to run. Hence, the string
+        "capture_stdio" has been used in this test case.
+        """
+        with capture.CaptureIO(self.logger, "capture_stdio"):
+            print("message 1")
+            sys.stdout.write("message 2")
+            sys.stderr.write("message 3")
+            sys.stdout.write("\xff")
+        log = self.handler.items
+        messages = [item["message"] for item in log]
+        self.assertIn("STDOUT: message 1", messages)
+        self.assertIn("STDOUT: message 2", messages)
+        self.assertIn("STDERR: message 3", messages)
+        self.assertIn(u"STDOUT: \xff", messages)
+
+
+if __name__ == "__main__":
+    mozunit.main()